MSK Flashcards
Which part of the join becomes infected in septic arthritis?
joint space
what age does septic arthritis commonly occur?
<2yrs
how can septic arthritis occur?
usually - haematogenous spread
puncture wound
infected skin lesions
adjacent osteomyelitis
What are the most common causative organisms of septic arthritis?
staph. aureus
What are the signs/sx of septic arthritis?
limp/pain referred to knee red hot tender joint reduced ROM febrile pseudo paresis
What is the criteria used to diagnose septic arthritis?
kosher:
fever >38.5
Non-weight bearing
Raised ESR + WCC
What is the definitive investigation for septic arthritis?
joint aspiration and culture
What are other investigations for septic arthritis?
- FBC - WCC, ESR/CRP
- blood cultures
- us of deep joints - joint effusion
- XR - normal in SA but will exclude trauma and bony lesions
What is the management of septic arthritis?
- IV flucloxacillin or clindamycin
- Joint wash out/ surgical drainage
- Keep joint immobilised in functional position at first then mobilise to prevent deformity
What is juvenile idiopathic arthritis defined as
persistent joint swelling >6 weeks presenting before 16yrs in absence of infection or any other cause
What are the subtypes and how are they classified?
→ Oligoarthritis = ≤4 → Polyarthritis = >4 joints → Systemic = incl. fever and rash → Psoriatic → Enthesitis → Subtyping further classified according to the presence of rheumatoid factor and HLA B27 tissue type
What are the symptoms of JIA?
Gelling
morning joint stiffness
pain
fever
What are signs of JIA in young child
intermittent limp
deterioration in behaviour/mood
avoiding fun activities
What is the cause of eventual swelling in JIA?
Joint effusion
inflammation
chronic due to proliferation of synovium
What are the effects of long term uncontrolled JIA?
bone expansion from overgrowth causing
valgus deformity
leg lengthening
discrepancy in digit length
What indicates sepsis or malignancy as a cause as opposed to JIA?
systemic features
What is the pharmacological management of JIA?
- NSAIDs, analgesics to relieve sx
- Joint injections
- Methotrexate
- systemic corticosteroids
- cytokine modulators e.g. TNF alpha blockers
What is important to monitor when giving methotrexate and why
regular bloods due to abnormal LFTs and bone marrow suppression
What are the complications of JIA?
- chronic anterior uveitis (visual impairment)
- flexion contractures of joints
- Growth failure
- Constitutional problems (anaemia, delayed puberty)
- osteoporosis
- Amyloidosis (rare)
What can be done to reduce risk of osteoporosis inJIA?
Dietary supplements of calcium and fit D
regular weight bearing exercise
minimal oral CS use
bisphosphonates???
Why is growth failure a complication of JIA?
anorexia, chronic disease and systemic CS therapy
What joints are commonly affected in oligoarthritis in JIA?
Knee
ankle
wrist
What is Perthes disease?
avascular necrosis of the capital femoral epiphysis of the femoral head to to interruption of the blood supply
followed by revascularisation and reossification over 18-36m
When does Perthes disease commonly present?
5-10yrs
What gender is perthes more common in and by how much?
boys 5x
What is the presentation of perthes disease? give the nature of onset
insidious
LIMP
hip/knee pain
stiffness, reduced ROM
What can perthes disease be confused w ?
transient synovitis
What are ix for perthes disease, what will they show?
Hip XR
early sign: increased density of femoral head
then becomes fragmented and irregular
What is the management of early perthes disease
bed rest and traction
What is the management of later perthes disease?
cover femoral head in acetabulum by maintaining hip in abduction
joint replacement due to risk of arthritis
What indicates a good prognosis of perthes disease?
younger (increased ability to remodel)
What is SCFE
slipped capital femoral epiphysis
Who is SCFE more common in?
10-15 yrs
obese boys
/What is SCFE associated w
metabolic endocrine abnormalities
e.g. hypothyroidism + hypogonadism
What is the presentation of SCFE
Either: acute or chronic
LIMP
hip pain (can be referred to knee)
what is found on examination in SCFFE?
restricted abduciton and internal rotation of the hip
How is SCFE diagnosed? what sign is seen?
Hip XR - trethowans sign
What is the management of SCFE?
Surgical pin
What is osteogenesis imperfecta also known as?
brittle bone disease
What is type 1 osteogenesis imperfecta? give the features
the milder and more common form
fractures during childhood
blue sclerae
some have hearing loss
What is type II osteogenesis imperfecta?
severe and lethal
multiple fractures before birth
many stillborn
What type of inheritance is osteogenesis imperfecta?
autosomal dominant
What is the underlying pathology of osteogenesis imperfecta?
disorder of collagen metabolism leading to bone fragility, bowing and frequent fractrues
What is the treatment of type I osteogenesis imperfecta
bisphosphonates
splinting of fractures to minimise joint deformity
